Compasses.



No. 723,720. PATENTED MAR. 24, 1903.

E. M. OS'I'LUND. I

COMPASSES.

APPLIOATION FILED SEPT. 11, 1902.

H0 MODEL.

Z 50 g O I anoemtoz Witness E- Z I m: Norms PETERS co. Pam's-Lima,WASHINGTON. 0.1:

UNITED ST TES PATENT OFFICE.

. ERIC M. OSTLUND, OF ROCHESTER, NEW YORK.

COMPASSES.

u SPECIFICATION forming part of Letters Patent No. 723,720, dated March24, 1903.

4 Application filed September 11,1902. Serial No.123,004. (No model.)

To all whom "it may concern.- Be it known that I, ERIC M. OSTLUND, ofRochester, in the county of Monroe and State of New York, have inventeda new and useful Improvement in Compasses, which improvement is fullyset forth in the following specification and shown in the accompanyingdrawings.

My invention belongs to a class of mechanics instruments commonly knownas compasses or dividers, used for taking, measuring, or subdividingshort distances or for striking circles or arcs of circles.

This improved instrument is formed with three legs equal in length, thepointed free ends of which being in a plane. The intermediate or middleleg of the device constitutes an integral part of the frame of theinstrument, carrying the two extreme or outside legs adapted to turn orswing on pivotal bearings on the frame independent of the intermediateleg and ofeach other.

The main object of the invention is to produce an instrument of thenature of compasses by means of which distances or measurements ofdilferent magnitudes may be carried between the points ofthe two pairs,of legs or a given idistance may be carried between the points of onepair of legs, While the distance between or measurementby the other pairmay be varied as need or use may require.

Other objects and advantages of the invention will be brought out andmade to appear in the following specification, reference being had tothe accompanying drawings, forming a part thereof, the invention beingparticularly pointed out in the claims.

Figure 1 is a side elevation of the compasses with one movable leg shownin two positions by full and by dotted lines. Fig. 2 is an edge Viewseen as indicated by arrow 2 in Fig. 1. Fig. 3 is an edge view of themiddle leg and frame detached, seen as indicated by arrow 2 Fig. 4 is aview of the device lookin Fig. 1.

Fig. 5 is a view ing down on top of the same.

from above, parts being horizontally sectioned on the dotted line 5 inFig. 1. Fig. 6, drawn to a reduced scale, is a side elevation of theframe detached. Fig. 7, exaggerated, is a transverse section of themiddle leg,taken on the dotted line 7 in Fig. 1.

In the drawings, A, Figs. 3 and 6, is a skeleton structure constitutingthe frame of the instrument, holding movable legs a c. This frameconsists of atapered bar or shaft'b, 'hav= ing a perforated head atoneend and pointed at the other, a short pintle e being held rigidly in thehead, as shown, the axis of the pintle being at right angles with theaxis of the tapered bar b. A curved strip d passes through alongitudinal opening't'in the bar I) I and made rigidtherein, this stripbeing in a frame, being held to place by tight-fitting washers h h onthe ends of the pin. These legs are formed with longitudinal openings k,Figs. 2, 4, and 5, through which to receive the ends of the curved stripd,'said strip constituting a guide for the outer legs, along which theyfreely move as they are turned one way or the other on the pivot-pin e.The instrument being thus constructed, the outer legs'a care free tomove toward or from the middle leg 1) independent of the latter and ofeach other and alternately act with said middle leg in two pairs-that isto say, the two legs a and b may act together as a pair in makingmeasurements, &c., and the two legs I) and 01 may likewise act as apair, either pair being independentof the other leg in either case.The'points of the three legs Ct 12 c are in the plane of the guide d.

Clamp-screws Z are provided for the movable legs a e to temporarily holdthese legs in their different positions of adjustment, the points of thescrews bearing against the side of the guide. I prefer also to make themiddle or skeleton leg b in sections, joined as shown, one sectionbeing-formed with a longitudinal axial socket m, Fig. 3, and the otherwith a reduced stem n to fit and fill the socket. This socket and thepart 'n. are preferably made polygonal in cross-section or otherwiseformed so the removable part will always take and occupy the samerelative position in the socket. A clamp-screw 0 of common kind isprovided to hold the joined parts of the leg I) together.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. Compasses consisting of a bar or shaft with head at one end andpointed at the other, a pin in the head of said bar, and a curvedguide-strip held to cross the bar, and legs held upon said pin, one oneither side of said bar and adapted to move toward or from the latteralong the guide-strip, and means for securing the legs in positions ofadjustment, substantially as and for the purpose set forth.

2. A frame for compasses; consisting of a headed bar, a pin in the headwith its axis at right angles with the axis of the bar, and a curvedstrip held rigidly in an opening in the bar, the plane of said stripcrossing the plane of the pin at right angles, the strip beingconcentric with the pin and extending equally each way from the bar, thelatter being in two sections joined, substantially as shown anddescribed.

3. Compasses consisting of a bar or shaft with head at one end andpointed at the other, a pin in the head of said bar, a guide-strip heldby the bar, and legs held movably upon the pin to traverse theguide-strip, and to coact with said bar, the legs being held to moveindependently of each other and of the bar, substantially as set forth.

4. Compasses consisting of a bar or shaft with head at one end andpointed at the other, a pin in the head of said bar, a guide-strip heldby the bar, and pointed legs held movably upon the pin to traverse theguide-strip, the legs and the bar being substantially alike in form andsize, said legs and the bar being adapted to act together in pairs,substantially as stated.

In witness whereof I have hereunto set my hand, this 8th day ofSeptember, 1902, in the presence of two subscribing witnesses ERIC M.OSTLUND.

Witnesses:

Enos B. WHITMORE, MINNIE SMITH.

